sedimentary

Iron-rich concretion or weathered ironstone nodule

Goethite–hematite-rich limonite concretion (tentative)

AI-generated identification · may be incorrect

Dark reddish-brown, dull to earthy luster, rounded and fine-grained; likely hardness about 4–6 Mohs and relatively high specific gravity (approximately 3–4). The prominent pale band may be a quartz/calcite-filled fracture or sedimentary vein, though the image cannot confirm mineralogy.

Identified August 17, 2026More sedimentary →

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Physical properties

Formation & geological history

Likely formed when iron oxides and hydroxides cemented sediment around a nucleus, followed by weathering and rounding; such concretions commonly form in sedimentary soils and rocks during the Cenozoic or older periods.

Uses & applications

Mostly a collecting specimen or landscape curiosity; ironstone and hematite may be mined as iron ore, but this individual nodule has no practical industrial value.

Geological facts

Its spherical shape and contrasting central seam are characteristic of a concretion or fractured nodule rather than a crystalline mineral specimen. A streak test and specific-gravity measurement would help distinguish hematite from limonite or magnetite.

Field identification & locations

Common in weathered sedimentary terrains, including parts of Australia, the United States, Europe, and South America. Check for a red-brown to black streak, weak magnetism, and a fracture-filled seam; avoid assuming it is a meteorite without testing.